Maximum Buffer Requirements for Wireline Fixed Availability Data

This article provides guidance to wireline ISPs on how to meet the maximum buffer requirements of the BDC. 

Providers of fixed wired broadband service must not exceed specific maximum buffer distances from their aggregation points to their served locations when reporting service availability based on their wired technologies.  Buffer distances from the aggregation point to the served location are measured in route distance and therefore must reflect where providers have deployed their last-mile distribution networks.   

The buffer distance from the aggregation point must include the drop distance.  The drop distance is a maximum of 500 feet from a deployed line or distribution network infrastructure to the parcel boundary of a served location.  The maximum buffer distance varies by the type of technology as follows: 


Digital Subscriber Line (DSL) offering speeds at 25/3 Mbps or greater 

The maximum buffer is a distance of 6,600 route feet from the DSLAM (DSL Access Multiplexer) to the covered premises.  

Hybrid-Fiber Coax (HFC) or cable  

The maximum buffer is 12,000 route feet from the aggregation point to the customer premises. 

Fiber to the Premises (FTTP or fiber)  

The maximum buffer is 196,000 route feet from the Optical Line Terminal (OLT) to the Optical Network Termination (ONT) 


These buffers are not safe harbors, and providers should report only areas or locations that they know to be serviceable by their networks.  If the locations that a provider can actually serve fall within a smaller distance from the aggregation point, then the provider should report only those smaller areas or sets of locations.  The buffers are maximum distances that wireline broadband service providers may not exceed in filing their availability data except where a specific exception applies. 

In their availability reporting, filers should include locations outside of the prescribed buffers only if:   

  • The filer has served a current or former subscriber using that technology; 
  • The locations are in an area in which the provider is receiving or has received universal service support to provide broadband service—or has other federal, state, or local obligations to make service available in the area—and the provider has begun to make service available in that area; or 
  • The Commission has granted a waiver to exceed the buffers based on a specific showing by the provider. 
Was this article helpful?
0 out of 0 found this helpful

Articles in this section

Video Resources
Key Reference Documents
BDC User Guide and Data Specifications
Form 477 Resources
Get Help